TY - JOUR
T1 - Functional analysis of the AKR4C subfamily of arabidopsis thaliana
T2 - Model structures, substrate specificity, acrolein toxicity, and responses to light and [CO2]
AU - Saito, Ryota
AU - Shimakawa, Ginga
AU - Nishi, Akiko
AU - Iwamoto, Tatsuya
AU - Sakamoto, Katsuhiko
AU - Yamamoto, Hiroshi
AU - Amako, Katsumi
AU - Makino, Amane
AU - Miyake, Chikahiro
N1 - Funding Information:
This work was supported by the Japan Society for the Promotion of Science (Scientific Research Grant no. 21570041, to C.M.) and the Ministry of Education, Culture, Sports, Science, and Technology of Japan (Scientific Research in Innovative Areas, no. 22114512, to C.M., and no. 21114006, to A.M.). We thank Professor Jun-ichi Mano (Yamaguchi University) and Dr. Yasuo Yamauchi (Kobe University) for generous advice.
PY - 2013
Y1 - 2013
N2 - In Arabidopsis thaliana, the aldo-keto reductase (AKR) family includes four enzymes (The AKR4C subfamily: AKR4C8, AKR4C9, AKR4C10, and AKR4C11). AKR4C8 and AKR4C9 might detoxify sugar-derived reactive carbonyls (RCs). We analyzed AKR4C10 and AKR4C11, and compared the enzymatic functions of the four enzymes. Modeling of protein structures based on the known structure of AKR4C9 found an (α/β)8-barrel motif in all four enzymes. Loop structures (A, B, and C) which determine substrate specificity, differed among the four. Both AKR4C10 and AKR4C11 reduced methylglyoxal. AKR4C10 reduced triose phosphates, dihydroxyacetone phosphate (DHAP), and glyceraldehydes 3-phosphate (GAP), the most efficiently of all the AKR4Cs. Acrolein, a lipid-derived RC, inactivated the four enzymes to different degrees. Expression of the AKR4C genes was induced under high- [CO2] and high light, when photosynthesis was enhanced and photosynthates accumulated in the cells. These results suggest that the AKR4C subfamily contributes to the detoxification of sugar-derived RCs in plants.
AB - In Arabidopsis thaliana, the aldo-keto reductase (AKR) family includes four enzymes (The AKR4C subfamily: AKR4C8, AKR4C9, AKR4C10, and AKR4C11). AKR4C8 and AKR4C9 might detoxify sugar-derived reactive carbonyls (RCs). We analyzed AKR4C10 and AKR4C11, and compared the enzymatic functions of the four enzymes. Modeling of protein structures based on the known structure of AKR4C9 found an (α/β)8-barrel motif in all four enzymes. Loop structures (A, B, and C) which determine substrate specificity, differed among the four. Both AKR4C10 and AKR4C11 reduced methylglyoxal. AKR4C10 reduced triose phosphates, dihydroxyacetone phosphate (DHAP), and glyceraldehydes 3-phosphate (GAP), the most efficiently of all the AKR4Cs. Acrolein, a lipid-derived RC, inactivated the four enzymes to different degrees. Expression of the AKR4C genes was induced under high- [CO2] and high light, when photosynthesis was enhanced and photosynthates accumulated in the cells. These results suggest that the AKR4C subfamily contributes to the detoxification of sugar-derived RCs in plants.
KW - Aldo-keto reductase (AKR)
KW - Methylglyoxal (MG)
KW - Plant diabetes
KW - Reactive carbonyls (RCs)
KW - Triose phosphate (TP)
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U2 - 10.1271/bbb.130353
DO - 10.1271/bbb.130353
M3 - Article
C2 - 24096666
AN - SCOPUS:84886702989
SN - 0916-8451
VL - 77
SP - 2038
EP - 2045
JO - Bioscience, Biotechnology and Biochemistry
JF - Bioscience, Biotechnology and Biochemistry
IS - 10
ER -
